| With the development of heavy-ion accelerator technology and detection technol-ogy, the heavy-ion fusion-evaporation reaction has become the most effective way to synthesize new element, especially new superheavy element. It has attracted much interest in recent years from both theoretical and experimental perspectives. In this work, the heavy-ion fusion-evaporation reactions,which are induced by weakly-bound stale nuclei, are calculated with the help of modern theoretical model of the heavy-ion fusion-evaporation reaction. The evaporation residue cross sections in the synthesis of very neutron-deficient nuclei are also studied. For details, see the following.Firstly, we introduce the modern theory of heavy-ion fusion-evaporation reaction. The theoretical models and their applicabilities are introduced respectively for the three stages of heavy-ion fusion-evaporation reaction (i.e., capture, fusion and evaporation).Secondly, a series of fusion-evaporation reactions induced by weakly-bound sta-ble nuclei are systematically studied, and the relevant ingredients of the reactions are discussed. It will be helpful for future study of the reactions induced by similar weakly-bound radioactive nuclei for the synthesis of neutron-rich isotopes of superheavy nu-clei. All the superheavy nuclei with Z≥112 produced experimentally up to now are neutron deficient. To produce their neutron-rich isotopes, one can use neutron-rich ra-dioactive nuclei as beams. The reactions induced by 6,7Li,9Be and 10,11B (bombarding 208Pb and 209Bi targets) are included in this work. The fusion cross sections are calcu-lated by coupled-channel model and the nuclear potential are chosen to match the shape of the fusion barrier distribution derived experimentally. The fusion cross sections are suppressed as a result of the breakup of projects and a survival factor was introduced for it. The compound nuclei decays are analyzed with the standard statistical model. The fission and evaporation residue excitation functions are well reproduced by our calculations, proving the applicability of the standard statistical model in describing the compound nuclei decay of this kind of nuclear reactions. For the compound nuclei with A=215-220 and Z=86-88, it is shown that a good description of the experimental data requires a scaling of about 0.80 to 1.02 for the rotating liquid fission barrier. And a drop in Bf with the increase of the fissionability parameter Z2/(50A) is also found. The fusion-fission cross sections which haven’t been measured experi-mentally are also given.An explosive nuclear synthesis near the drip line produces proton-rich unstable nuclei, which can be used to study physics under extreme conditions. This represents one of the most active areas of research in modern nuclear physics. The experimental researches of the very neutron-deficient rare-earth nuclei via fusion evaporation reac-tion between stable nuclei were undertaken recently, such as 32S+92Moâ†'124Ce,36Ar +92Moâ†'128Nd,36Ar+96Ruâ†'132Sm,36Ar+96Ruâ†'132Sm,40Ca+97Moâ†'137Sm,32S +106CDâ†'138Gd, 36Ar+106Cdâ†'142Dy, 40Ca+106Cdâ†'146Er and 40Ca+112Snâ†'152Yb. Since the products of these reactions are nuclei near the proton drip line, it is difficult to measure and it has been measured at just one serval energy points. Thus the empirical model is applied to calculate their fusion cross sections as it has few free parameters. For the calculation of evaporation residue cross sections, the input parameters a and af/an were carefully chosen according to the experimental data and other theoretical calculations. The fission barrier scaling factor kf was left as the only free parameter. We found that the fission barrier scaling factor should be greatly reduced to reproduce the experimental data. It is in accordance with the early studies of the synthesis of neutron-deficient isotopes. |
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